The costumes look remarkably grand for home theatricals, the jewellery is startlingly convincing, and the band evidently comprises moonlighting members of the Royal Horse Guards. The principal boy's legs, in silk stockings, are absolutely tremendous.

An album of photographs preserved in mint condition for more than half a century by a Windsor schoolboy who starred in Christmas pantomimes also shows his fellow cast members: they include Aladdin, played by one Elizabeth Windsor, and her sister, Margaret, as, appropriately, a princess. The auditorium was the vast splendour of the Waterloo Chamber at Windsor Castle.

The pantomimes were performed during 1941-44, a period when the princesses had been sent for safety to live in Windsor, while their parents looked the East End in the face by staying on in Buckingham Palace while bombs rained down on central London. The families were usually together at weekends, and one photograph shows the princesses in rehearsal, being prompted by the Queen Mother. The stars are children in the first photographs, young women in the last.

The photographs, never exhibited or published before, together with signed programmes, are coming up for auction next week at Dominic Winter auction house in Gloucestershire, and are estimated to fetch around £16,000.

The sisters first appeared in a charity concert raising funds for the troops, and it was apparently Princess Margaret – a showbiz enthusiast for the rest of her life – who proposed that they tackle a pantomime. The albums were compiled by Hubert Tanner, head of the local school, who wrote and directed all the shows – although the last, in 1944, Old Mother Red Riding Boots, is perhaps diplomatically listed as "devised by Princess Elizabeth, Princess Margaret and Hubert Tanner". The Queen often played male roles, including Aladdin, and Prince Florizel to her sister's Cinderella.

Tanner died soon after the war, and the albums were inherited by one of his star pupils, Cyril Woods, who had appeared in all the shows, and kept them all his life. He worked for the crown estate, and remained a friend of the family until his death in 2001.

At the auction house, senior valuer Chris Albury said it was an exceptional collection. "You see the odd signed photograph, the odd programme, but to have this many really is remarkable. It is a lovely collection because it really shows the end of childhood for the young princesses."